Grinding machines



Dec. 17, 1957 A, FF 2,816,401

GRINDING MACHINES Filed June 20, 1955 3 Sheets-Sheet 1 INVEMOR m mm g 1 am 4 ATTORNEYS Filed June 20, 1955 3 Sheets$heet 2 v ATTORNEYS Dec. 17, 1957 R. A. DUFF 2,816,401

GRINDING MACHINES Filed June 20, 1955 3 Sheets-Sheet 3 ATTORNEYS United States Patent GRINDING MACHINES Robin Airlie Duff, Rock Hill, Wolverley, near Kidderminster, England, assignor to F. H. Lloyd & Co. Limited, James Bridge Steel Works, near Wedneshury, England, a British company Application June 20, 1955, Serial No. 516,693

4 Claims, (Cl. 51-99) This invention has reference to improvements connected with grinding machines and is particularly applicable to machines wherein the grinding wheel is rotatably mounted on a swinging or traversable derrick, so that the wheel can be brought into the required position relative to the work, the work being mounted on a traversable turntable.

The objects of the invention are to reduce the amount of manual effort and control to be exercised by the operator, to provide initial setting adjustments and controls which ensure a more accurate grinding operation and the incorporation of means for reducing or eliminating the amount of dust escaping to atmosphere as a result. of the grinding operation.

The invention consists of a grinding machine wherein the grinding wheel is rotatably mounted on a swinging derrick which is capable of permitted longitudinal reciprocal motion on a traversable main carriage mounted on the machine pedestal, an operators seat mounted on said derrick, an independent motor drive for effecting anadjustable reciprocal traverse of the derrick, an operating shaft control for the traverse of the mounting of an adjustable stop to determine the permitting grinding depth, a rotatable work table support mounted on a traversable undercarriage on the main table, automatic interlocking and braking means interconnecting the work table support and the undercarriage, and said undercarriage and main table, and a dust extraction receptable adapted to be positioned relative to the grinding station of the machine.

A preferred means of carrying the present invention into practice will now be described with particular reference to the accompanying drawings, in which:

Fig. 1 is an elevation of the machine with certain parts thereof removed for clarity, the omitted parts being shown in detail in Figs. 3 and 4.

Fig. 2 is a plan of Fig. 1.

Fig. 3 is a part sectional elevation on line 33 of Fig. 2.

Fig. 4 is an end elevation of Fig. 3 looking from the lefthand side.

Fig. 5 is a part sectional enlarged view illustrating the means of rotatably mounting, interlocking and braking the work table support and the undercarriage on the main table.

The grinding wheel a is rotatably mounted on a motordriven shaft b which in turn is mounted on a swinging derrick c which derrick is capable of a limited traversable motion on a pair of flanged wheels d mounted on a short track e which track in turn forms part of the upper surface of a traversable carriage e mounted by means of two pairs of wheels e on another track which forms part of the main pedestal g of the machine, which pedestal is rotatable on flanged rollers 11 mounted in brackets h which are secured to the floor on which the machine is located, thus providing for rotational motion of the der rick c in a horizontal plane. Within this traversable carriage 2 (see more particularly Figs. 3 and 4) there is mounted on a bracket e a small electric motor j which is "ice coupled through a chain or belt drive k to a crank shaft I pivotally' connected at its one end to a connecting rod m which rod at its other end is pivotally connected to a slotted segment 22 which is pivotally mounted on a bracket e which is mounted on the traversable carriage e. Located within the slot in the segment n is one end of a connecting link 0 which at'its other end is pivotally connected to a forked bracket p which is formed by two parallel slide plates which are secured to a horizontally slidable rod q traversable within a pair of brackets e mounted on the carriage e, the upper forked end of the bracket p provides a connection between the bracket 12 and the axle d of the wheels d which traversably support the derrick 0.

Connected to the one end of the derrick by means of a bracket c is a cranked tubular extension 0 which provides a support for the seat r to accommodate the operator of the machine whereby his weight is efiiectively added to the pressure which can be applied by the grinding wheel a to the work and this pressure can within reasonable limits be adjusted by the physical movement of the operator.

In order to determine the permitted degree of grinding depth allowed to the grinding wheel a there is mounted on the cranked part of the tube c a screwed rod s which at itslower end carries a supporting wheel s which bears on a plate I supported on the floor mounting of the machine. The rod s is operated by means of a spoked wheel a which is in convenient proximity to the seat r for convenience' of operation. Also in proximity to the front of the seat e is a hand rail 0 which extends from the tubular extension 0 Referring now more particularly to Fig. 5 of the drawings, the work is adapted to be mounted on one of two alternative ball-bearing table supports v disposed on a main slotted turntable w through the medium of an undercarriage v which is capable of traversable motion by means of two pairs of wheels v in parallel track slots W formed in the main turntable w. The table supports v and the undercarriages v may be said to constitute bogies which are provided with hand lever control devices 11 part of each lever automatically functioning as brake locks to prevent both rotary motion of the table support for the work relative to the undercarriage and traversable motion of the undercarriage relative to the main turntable. This locking and braking operation is eifected by the engagement of the lower limb of the hand lever 1 within one of a series of slots 'v annularly dis posed in the depending peripheral flange of the table v, the limbs of each hand lever being inherently resilient and adapted to automatically engage within the slots v in order to interlock the parts v and v in the required relationship, and when these parts are so locked a braking motion is applied to the wheels v to prevent traverse of the table supports v, v relative to the main turntable w.

The alternative work table supports and the undercarriage on which they are rotatably mounted are similar in design in order that while the operator is functioning on one piece of work another piece of work can be assembled on the other table support in readiness for a sequence operation, the relative arrangement of these table supports and the main turntable are clearly seen in the plan view Fig. 2.

It is to be appreciated that by the aforesaid arrangement not only has the operator effective control over the degree of pressure which can be applied to the grinding wheel and therefore to the Work, but that he has ready control of the permitted longitudinal traversable motion of the grinding wheel on its derrick support.

In order to provide for the initial setting of the derrick carrying the grinding wheel in relation to the work to be done, there is provided a motor y which is rigidly suspended from the traversable carriage e. This motor drives a screw shaft 32 which has location within a fixed tapped bearing z extending from the bracket g forming part of the pedestal g of the machine, thus when the motor y is set in operation the rotation of the screw y within the tapped bearing z effects a traverse of the carriage along the track to position the derrick and its superstructure to the required initial setting position of the grinding wheel a to the work on one or other of the Work tables v.

Adapted to be closely associated with the grinding machine in a position adjacent the periphery of the grinding wheel a is a hooded dust extractor booth x which can be positioned so as to receive the wheel a and the bulk of the dust patricles removed from the work by the operation of the grinding wheel so as to avoid the escape to atmosphere of the dust particles in the process of the grinding 1 operation.

I claim:

1. A grinding machine comprising in combination a derrick carrying a grinding wheel, a carriage on which the derrick is mounted to rock on a transverse axis to reciprocate, a pedestal mounted for rotation on a vertical axis and on which the carriage is mounted for angular traverse in a horizontal plane and for longitudinal traverse in parallelism with the longitudinal axis of the derrick, a motor mounted on the carriage, means operative by said motor for imparting reciprocatory motion to the derrick relative to the carriage, a main turntable mounted for rotation on a vertical axis, a plurality of alternative Worktable supports mounted for rotation and for longitudinal traverse on said turntable, the derrick being adjustable relatively to the turntable and worktable supports to position the grinding wheel for angular traverse and reciprocation on any desired longitudinal axis and to traverse an arcuate path in relation to a workpiece on one or another of the worktable supports, a rigid extension from an end of the derrick and beyond the grinding wheel and carrying a seat on which the operator of the machine may distribute his weight to vary the pressure of the grinding wheel on a workpiece on a worktable support, and a downward extension from said extension from said end of the derrick having means for adjusting the height of the grinding wheel in relation to the workpiece on a worktable support,

4 and a traversable mounting on the lower end of said downward extension for determining the grinding depth of the grinding Wheel.

2. A grinding machine as defined in claim 1, including nndercarriages on which said worktable supports are mounted rotatably, tracks on said main turntable, wheels on and supporting each undercarriage and traversably mounted on respective tracks, and means for locking each worktable support from rotation relatively to its undercarriage and for simultaneously braking the wheels of the undercarriage on their tracks.

3. A grinding machine as defined in claim 1, wherein said means for imparting reciprocatory motion to the derrick relative to said carriage comprises a slotted segment pivoted on said carriage, a crank connected to said segment for rocking it on its pivot, an independent electric motor mounted on the carriage for operating said crank, and a link connected at one end to the derrick and having means at its other end adjustably engageable in the slot in the segment for Varying the amplitude of the reciprocatory motion imparted to the derrick.

4. A grinding machine as defined in claim 3, including a further electric motor and means operable thereby for effecting longitudinal adjustment of the position of said carriage relatively to said pedestal.

References Cited in the file of this patent UNITED STATES PATENTS 1,219,670 Schlueter Mar. 20, 1917 1,301,190 Stowell Apr. 22, 1919 1,378,473 Lareau May 17, 1921 1,462,420 Mikaelson July 17, 1923 1,488,564 Steinle Apr. 1, 1924 1,493,787 Little May 13, 1924 1,725,899 Chase Aug. 27, 1929 2,015,495 Philippi Sept. 24, 1935 2,244,586 Venable June 3, 1941 2,418,737 Talboys Apr. 8, 1947 2,726,490 Lowe Dec. 13, 1955 2,741,070 Muehling Apr. 10, 1956 2,750,714 Muehling June 19, 1956 

